如何在pytorch对象检测中添加变换

Question

我是PyTorch&通过PyTorch对象检测文档教程PyTorch-docx。在他们的collab版本中，我做了以下更改以添加一些转换技术。

1. 首先更改类PennFudanDataset(torc.utils.data.Dataset(的__getitem__方法

if self.transforms is not None:
img = self.transforms(img)     
target = T.ToTensor()(target)
return img, target
In actual documentation it is 
if self.transforms is not None:
img, target = self.transforms(img, target)  

其次，在get_transform(train)函数上。

def get_transform(train):
if train:
transformed = T.Compose([             
T.ToTensor(),
T.GaussianBlur(kernel_size=5, sigma=(0.1, 2.0)),
T.ColorJitter(brightness=[0.1, 0.2], contrast=[0.1, 0.2], saturation=[0, 0.2], hue=[0,0.5])
])
return transformed
else:
return T.ToTensor()
**In the documentation it is-** 
def get_transform(train):
transforms = []
transforms.append(T.ToTensor())
if train:
transforms.append(T.RandomHorizontalFlip(0.5))
return T.Compose(transforms)

在实现代码时，我得到了以下错误。我不能理解我做错了什么。

TypeError: Caught TypeError in DataLoader worker process 0.
Original Traceback (most recent call last):
File "/usr/local/lib/python3.6/dist-packages/torch/utils/data/_utils/worker.py", line 198, in _worker_loop
data = fetcher.fetch(index)
File "/usr/local/lib/python3.6/dist-packages/torch/utils/data/_utils/fetch.py", line 44, in fetch
data = [self.dataset[idx] for idx in possibly_batched_index]
File "/usr/local/lib/python3.6/dist-packages/torch/utils/data/_utils/fetch.py", line 44, in <listcomp>
data = [self.dataset[idx] for idx in possibly_batched_index]
File "/usr/local/lib/python3.6/dist-packages/torch/utils/data/dataset.py", line 272, in __getitem__
return self.dataset[self.indices[idx]]
File "<ipython-input-41-94e93ff7a132>", line 72, in __getitem__
target = T.ToTensor()(target)
File "/usr/local/lib/python3.6/dist-packages/torchvision/transforms/transforms.py", line 104, in __call__
return F.to_tensor(pic)
File "/usr/local/lib/python3.6/dist-packages/torchvision/transforms/functional.py", line 64, in to_tensor
raise TypeError('pic should be PIL Image or ndarray. Got {}'.format(type(pic)))
TypeError: pic should be PIL Image or ndarray. Got <class 'dict'>

Answer 1

我认为Pytorch变换只对图像(在这种情况下是PIL图像或np数组(有效，而对标签(根据跟踪，标签是dict(无效。因此，我认为你不需要；tensorify"；如在CCD_ 4函数中的该行CCD_。